Like daffodils, tulips are an iconic flowering spring bulb, filling gardens with color well before most other flowering plants have gained momentum. The plants have two to six broad, strappy leaves with a waxy coat that gives them a blue-green color. The flowers are usually cup-shaped, with three petals and three sepals. Some tulips are star-shaped or goblet-shaped.
Tulips are among the oldest cultivated plants and have been hybridized to produce just about every color except for true blue. Most tulips have one flower per stem, but a few are multi-flowering. There are literally thousands of different types of tulips spread over 15 official classifications based on flower shape, height, and time of bloom.
Although tulips are perennial bulbs, many hybrid types tend to be rather short-lived. Keeping a massive display of tulips requires planting additional bulbs each fall for the following spring's showcase. And because tulips require a chilling period, gardeners in warmer climates must purchase pre-chilled bulbs and plant them afresh each year. But even if you have to grow your tulips as annual plants, they will still lift your spirits in the spring. Once they emerge from the ground, tulips grow and flower quickly. In cold-winter climates, they typically emerge in March and begin flowering in April to May.
|Botanical Name||Tulipa (Group)|
|Plant Type||Perennial flowering bulb|
|Mature Size||9 to 24 inches tall (depending on type)|
|Sun Exposure||Full sun|
|Soil Type||Rich, medium-moisture, well-drained soil|
|Soil pH||6.0 to 7.0|
|Bloom Time||April to May|
|Flower Color||All colors except blue|
|Hardiness Zones||3 to 8|
|Native Area||Originally from Central Europe and Eastern Asia; now widely cultivated and hybridized|
|Toxicity||Toxic to humans and pets|
Tulips grow best as perennials in climates with moist, cool-to-cold winters and warm, dry summers. Plant the bulbs 4 to 8 inches deep in the fall (a depth about three times the size of the bulbs), in a sunny location with well-drained soil. Because they sprout and bloom so early in the spring, tulips can work well beneath trees and shrubs that will leaf out to create shady conditions later in the season. Space the bulbs 2 to 5 inches apart (depending on their size), with the pointy end facing up. Tulips tend to display best if planted in groups of about 10 bulbs.
Tulips are sometimes grown as annuals—especially the hybrid varieties. In this case, you can dig up and discard the bulbs after blooming is complete, then plant summer flowers in their place. In warmer climates, this is the typical way to grow tulips—purchasing pre-chilled bulbs from commercial sellers and planting them in early spring. Since the bulbs will not naturally chill over the winter, you have to start with new bulbs each spring.
If you are growing tulips as perennials, be aware that many varieties, especially the hybrids, will begin to decline after two years, or so. Species varieties, on the other hand, will continue to bloom vigorously each year and may reproduce themselves with offsets that can be divided to provide more plants. When growing tulips as perennials, remove the flower stalks immediately after they flower, but leave the foliage in place until it turns yellow. This helps replenish the bulb's energy.
All varieties of tulips prefer full sun.
Tulips prefer rich, well-draining soil with a pH that is neutral to slightly acidic. Mixing in compost can improve drainage and provide nutrients to the bulbs. Ideally, do this before planting the bulbs. Otherwise, you can apply a few inches of compost over the soil to encourage earthworms to tunnel into the soil, improving circulation and tilth.
Water the bulbs thoroughly immediately after you plant them, but after this withhold watering except during extended dry spells. If your region gets some rain every week or two, don't water your tulips at all. In arid regions, watering every two weeks is recommended. Tulips are native to dry regions in central Europe and Eastern Asia, so the more closely you can approximate those conditions, the longer your tulips will last.
Temperature and Humidity
Tulips thrive in regions with cool-to-cold winters and dry, warm summers. They require 12 to 14 weeks of temperatures below 55 degrees Fahrenheit in order to bloom, so in regions without cool winter temperatures, they must be planted as annuals.
Tulips tend to do better in dry regions rather than humid climates, since high humidity usually goes hand-in-hand with lots of spring and summer rain, which can cause bulbs to rot.
Add some compost, bone meal, or granular fertilizer to the planting hole when you plant the tulip bulbs. Feed them again the following spring, when they sprout again. Other than this, no feeding is necessary.
Are Tulips Toxic?
Tulips, particularly the bulbs, are toxic to humans and pets if ingested in large quantities. However, their level of toxicity is considered mild.
Symptoms of Poisoning
Dogs that eat multiple tulip bulbs may experience the following symptoms:
- Nausea and vomiting
- Diarrhea or gastrointestinal irritation
- Increased heart rate or respiratory rate
- Difficulty breathing
There is some historic evidence of humans eating moderate amounts of tulip bulbs (up to five bulbs) with few or no symptoms. However, the bulbs should not be considered edible. Handling bulbs with bare hands for extended periods can cause a condition known as "tulip fingers," an allergic reaction that results in a painful rash and can make the fingernails brittle, possibly separating from the nail bed. The best prevention is for sensitive individuals (not everyone is susceptible) is to wear nitrile (not latex) gloves when working with tulip bulbs.
- 'Purissima' (Fosteriana division): Very early, pale yellow petals that fade to white
- 'Ballarina' (Lily division): Fragrant with flared, pointed, orange petals
- 'Ballarina' (Fosteriana division): Sunny yellow with white tips that look like feathers
- 'Prinses Irene' (Triumph division): Rembrandt-style orange petals streaked with burgundy
- 'Spring green' (Viridflora division): White petals with green center stripes; late-blooming and long-lasting
Classification of Tulips
The variety of tulips available is somewhat bewildering, since there are 15 separate divisions based on characteristics such as plant size, bloom time, flower shape, and genetic origin:
- Single early: Cup-shaped with one flower per short stem; first tulips to bloom, starting late March
- Double early: More than the usual number of petals, with a fluffy appearance; tall stems (12 to 15 inches); start blooming in early April; can be harmed by cold snaps and winds
- Triumph: Cross between early and late singles; tall stems (15 to 18 inches); late-April bloomers
- Darwin hybrid: Cross between Darwin and Fosteriana; tall stems (24 inches) and very hardy; naturalize well; late-season, blooming into May
- Single late: One bloom per stem; known for a wide range of colors and late-season bloomers
- Lily-flowered: Tall (18 to 24 inches), late-season bloomers with pointed, slightly flared petals
- Fringed: Fringed or ruffled petal edges in many colors, sometimes with contrasting colors on the fringe; late-season bloomers with 12- to 18-inch stems
- Viridiflora: Late season blooms on 12- to 24-inch stems with distinctive green streaks in their petals
- Rembrandt: Once prized for their colorful streaks and mottling; no longer grown commercially because the coloring was caused by a virus that spreads to other tulips; plants now advertised as 'Rembrandt' are cultivars that mimic the look of the originals
- Parrot: Named for the bud's resemblance to a parrot's beak; flowers are large, with twisted, curling petals on tall stems (12 to 24 inches); late-season blooms
- Double late: Also called peony tulips; tall stems (18 to 24 inches) with enough petals to rival a peony bloom; not particularly hardy but work well in containers
- Kaufmanniana: Also known as the water lily tulip; early bloomers with wide-open flowers that are almost flat; leaves have brownish-purple mottling; short plants, only 6 to 12 inches tall
- Fosteriana: Also known as emperor tulips; large flowers, often with pointed petals and available in many colors; bloom mid-season; plant 8 to 15 inches tall
- Griegii: Short (8 to 12 inches), early-season bloomers with flared, pointed petals and wavy leaves; brightly colored, including some bi-colors
- Species or wild tulips: Great for perennializing; short plants (4 to 12 inches) with lots of variety and varying bloom times
While tulips can be propagated from seeds, the more common way to do it is by lifting the bulbs and dividing the offset bulbs (bulblets) that are attached to the mother bulb. This should be done in the fall, at the normal planting time for tulips.
- Dig up the bulbs with a trowel or spade, then brush off the soil and gently break off the small offset bulbs from the mother bulb.
- Inspect the offsets and discard any that appear soft or deformed.
- Replant the offsets and the mother bulb at a depth about three times the diameter of the bulb, with the pointed side facing up.
For the first few years, the new tulips will produce foliage but no flowers. At about the third year, you can expect the new bulbs to bloom.
Tulip bulbs and foliage are popular with many animals, including deer, squirrels, and other rodents. In some areas, it's just not worth planting tulips in the ground, and you're better off growing them in protected containers. Alternatively, you can try deterrents or interplant the tulips with daffodils, but be prepared to lose a few.
Tulips are susceptible to basal rot and fire fungus. Basal rot appears as dark brown spotting or as pink or white fungus on the bulbs. Plants that grow from affected bulbs may be deformed and/or die early. The best remedy is to discard affected bulbs and plant new bulbs that have been treated with a fungicide.
Bulbs affected by fire fungi lead to malformed or stunted plants or plants that never emerge. Affected plants may have curling shoots or dead areas with dark green rings. Treat affected plants with a fungicide. Discard affected bulbs, and plant new bulbs that have been treated with a fungicide.
Design Suggestions for Tulips
There aren't that many flowers in bloom when tulips put on their show, so they can be worked into any spot in the yard. They look best when planted in clusters, rather than lines. They make good companions for other spring bulbs, like Chionodoxa (Glory of the Snow), late daffodils, dwarf iris, and Scilla.
Some of the cool-season annuals, like snapdragons and pansies, provide a nice contrast to the bowl shape of tulip flowers. The blues of Forget-Me-Nots and Virginia Bluebells (Mertensia virginica) play up the bold colors of tulips.
Tulips also make great cut flowers. If a deer problem prohibits you from growing tulips in your yard, you could grow them in your fenced vegetable garden and bring them indoors to enjoy.